From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] virtio-scsi spec: add per-LUN parameter query Date: Mon, 20 Aug 2012 15:18:30 +0200 Message-ID: <50323926.8000205@redhat.com> References: <1345453404-15244-1-git-send-email-mc@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1345453404-15244-1-git-send-email-mc@linux.vnet.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Cong Meng Cc: stefanha@linux.vnet.ibm.com, zwanp@cn.ibm.com, linuxram@us.ibm.com, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org Il 20/08/2012 11:03, Cong Meng ha scritto: > Each virtio scsi HBA has global request queue limits. But the passthrough > LUNs (scsi-generic) come from different host HBAs may have different request > queue limits. If the guest sends commands that exceed the host limits, the > commands will be rejected by host HAB. > > To address this issue, this patch adds a per-LUN parameter query via the control > queue, and defines some parameter query types. The driver can query and set the > needed per-LUN parameters if the device enables this feature. > > Signed-off-by: Cong Meng > -- > virtio-spec.lyx | 218 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 218 insertions(+), 0 deletions(-) Do you have kernel and QEMU patches for this? That would help me evaluate whether the interface is the correct one. In any case, I'd rather have a single command returning all three values (VIRTIO_SCSI_T_LUN_QUEUE_PARAMS), since it's unlikely that you need just one. Paolo